Linggu Cave, about 30 kilometers southwest of Yixing, is only 6 kilometers away from Zhanggong Cave. It is a giant lime karst cave. The whole cave is more than 8,300 square meters in size and more than 1,200 meters in length. It is said that Linggu Cave was discovered by Tang Dynasty poets, turtles and Meng tea exploration. Lu Zeng hired people to dig, because the engineering ability can not be reached and stopped, leaving "Mr. Gui Meng Zhi unpaid, Tang and Song have not worn the heart" regret. After the Song, some people entered the cave to explore the secluded, and there are still ink left by Song, Yuan, Ming and Qing tourists on the stone wall.